Hi Rob,
This is a common complaint amongst hosts and the reason is that Airbnb have search algorithms that are a bit of a mystery but ultimately mean that although your listing isn't showing to you that doesn't mean it isn't showing your listing to others.
As there are many available listings Airbnb try to show your listing to people who are most likely to book your place. If a family is searching in your area and have a history of booking luxury accommodation they will show luxury options. Alternatively if a family has a history of booking more budget friendly options, they will show family friendly budget options. Ironically they may not match you with your own property!
As ever these tech giants hold a huge amount of data on their users: what properties you have saved in your wishlists, which properties you have clicked on and booked and then how you have rated them and this all builds a profile of the styles of properties you like and will likely book. Which in turn influences what appears in your searches for future properties.
Your best indicator if your property is showing up to potential guests is by looking in your "progress" tab at the top of the page and looking at "views".
Hope that is helpful!
Emily